• Journal of the Korean Geotechnical Society
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• v.20 no.8
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• pp.113-121
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• 2004

The present study is suggested to estimate the degree of secondary consolidation caused by various changes of stress such as loading, unloading and reloading in improving poor subsoil through pre-compression loading construction method and, for this purpose, examined the characteristics of the consolidation of Kunsan clay through incremental loading test (IL) using standard consolidation tester and constant loading rate test (CLR), which were adapted from the constant rate of strain test (CRS). In addition, after CRS test, this study determined the characteristics of secondary consolidation and relationships among void ratio, effective stress and time according to the ratio of effective over-consolidation on reloading at the point of time of random expansion. Kunsan clay had larger expansion and smaller secondary consolidation settlement when the ratio of effective over-consolidation was high. In addition, when loading was applied after the load was removed at once, the secondary consolidation coefficient $C'_{\alpha}$ was smaller than that when the load was removed gradually, and when the ratio of effective over-consolidation was over 1.4 a similar value was produced. Based on the entire settlement resulting from reloading, the secondary consolidation coefficient $C"_{\alpha}$ increased non-linearly with the lapse of time but the final value was similar to that in the case of rapid removal. The strain velocity of void ratio was in a regular linear relationship with the increase of loading time regardless of the ratio of effective over-consolidation in both tests and it grew smaller with the increase of the ratio of effective over-consolidation.tion.

• Journal of the Korean Geotechnical Society
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• v.20 no.9
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• pp.105-114
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• 2004

Consolidation characteristics have been investigated by using Rowe cell consolidation tester for dredged soil, which is more than two times as much as the liquid limit. To examine the effects of variation of water content on consolidation characteristic, tests were carried out varying the initial water content from $100\%\;to\;150\%.$ The results were compared with the consolidation characteristics of remolded clay. The test results showed that the hither the initial water content of dredged clay was, the more noticeable the non-linear behavior of e-log P curves occurred. The variation of the gradient was apparent to load stage 40kPa and became less apparent after load stage 80kPa on the e-log P curves. Ratio of compression index stayed within the range suggested by Mesri and variation of initial water content has hardly influenced the coefficient of consolidation. On the contrary, it was found that the magnitude of consolidation load affects the vertical coefficient of consolidation. The variation of stratum thickness during consolidation processing needs to be taken into consideration since hydraulic fill would go through a much larger scale strain than land soil when it is subject to a load. In this study, the consolidation period considering the variation of stratum thickness was analyzed and the results were compared with those of existing consolidation studies which did not consider the variation of stratum thickness. According to the results of the study, the consolidation period of the ground with a larger strain was calculated more close to observed value in case of Mikasa theory which takes the variation of stratum thickness into consideration.

• Journal of the Korean Society of Clothing and Textiles
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• v.19 no.4
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• pp.684-695
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• 1995

The purpose of this study was to investigate the influence of the mechanical properties on drapability in the peach skin-like finished fabrics. For this study, the samples used were 50 kinds of peach skin-like finished fabrics. The mechanical properties such as tensile, shearing, bending, compressional, surface characteristic values, thickness and weight were measured with a KES-F system and drupe coefficient by drape tester. The relationship between the characteristic values and drape coefficicients of the peach skin-like finished fabrics results were obtained. 1. Peach skin-like finished fabric had $\pm$2o range of shearing, bending, compression, surface. properties, thickness and weight as compared with Japanese women's thin fabrics. The characteristic mixing values were better with the values of WC/T, W/T, etc. as compared with that of japanese women's thin fabrics. Accordingly, the peach skin-like finished fabrics had a little volume, excellent hanging and drapability as compared with japanese women's thin fabrics. 2. The drape coefficient of peach skin-like finished fabric had a high level of correlation between 2HB, G, WC, MIU, WT, MMD, 2HG, RT, W, B etc. of the mechanical properties. The blocked properties that contributed to the drape coefficient of peach skin-like finished fabrics were in the order of the bending> tensile> thickness> weight properties. This drape coefficients(DC) were found by measuring the mechanical properties according to the obtained regress on equate on. DC=99.0179+17.9023 log G -17.0543 log 2HG5+17.2104 log 2HG+35.7685 log 2HB+ 4.6082 log B-30.5906 log T+4.2308 log W 3. The contribution to the drape coefficient of the characteristic mixing values of peach skin-like finished fabric was in the order of > 2HB/W> 2HB/B> B/W The drape coefficients were found by measuring the characteristic mixing values according to the obtained regression equation. 4. The drape coefficients of peach skin-like finished fabrics were influenced by the differences between the bending of warp direction, bending of weft direction, shearing etc which in turn determine the level of hanging. The regression equation was as follows; 5. The drape coefficients of peach skin.like finished fabrics had a highly positive correlation with the node index. It has an negative correlation with number of nodes.